There is a lot of dust under the glass of my iphone. Went to Mac store. Genius said it could be replaced for free, then he said "wait" and showed me a crack in the back (where I dropped it one time) and said it would be $199.00 to replace. Should, I suck it up and continue to use it with dust under the glass (not that bad yet) or buy a new one for $199.00? or any other ideas?